Pre-doped anodes and methods and apparatuses for making same

Abstract

An energy storage device can include a cathode, an anode, and a separator between the cathode and the anode, where the anode can have a desired lithium pre-doping level to facilitate desired capacitor performance. Controlled anode pre-doping can include printing lithium powder or a mixture including lithium powder onto a surface of the anode. Controlled anode pre-doping can include electrochemically incorporating lithium ions into the anode. A duration of the pre-doping process can be selected such that desired anode pre-doping is achieved.

What is claimed is: 
     
         1 . An energy storage device comprising:
 a cathode;   an anode comprising intercalated lithium ions; and   a separator between the cathode and the anode;   wherein the intercalated lithium ions are present in an amount selected to limit lithium metal plating and to limit gassing; and   wherein the amount of intercalated lithium ions corresponds to an anode voltage of about 0.05 to about 0.3 V compared to an Li/Li +  reference voltage.   
     
     
         2 . The energy storage device of  claim 1 , wherein the energy storage device has an open circuit cell voltage of 2.7 V to 2.95 V following pre-doping and before use. 
     
     
         3 . The energy storage device of  claim 1 , wherein the lithium metal plating occurs at an anode voltage of about 0 V compared to an Li/Li +  reference voltage. 
     
     
         4 . The energy storage device of  claim 1 , wherein the gassing occurs at a cathode voltage of about 4 V compared to an Li/Li +  reference voltage. 
     
     
         5 . The energy storage device of  claim 1 , further comprising an electrolyte comprising a lithium salt. 
     
     
         6 . The energy storage device of  claim 5 , wherein the electrolyte further comprises a carbonate. 
     
     
         7 . The energy storage device of  claim 1 , wherein the anode comprises an electrode film mixture comprising a carbon material selected from graphite, hard carbon, and soft carbon. 
     
     
         8 . The energy storage device of  claim 1 , wherein the anode comprises an electrical conductivity promoting material. 
     
     
         9 . The energy storage device of  claim 1 , wherein the energy storage device is a capacitor. 
     
     
         10 . The energy storage device of  claim 1 , wherein the anode comprises a dry, free-standing electrolyte film and a current collector. 
     
     
         11 . An energy storage device comprising:
 a first electrode comprising lithium ions adsorbed to a first electrode surface;   a second electrode;   a separator between the first electrode and the second electrode; and   an electrolyte comprising a lithium salt;   wherein the lithium ions are present on the first electrode surface in an amount corresponding to a first electrode voltage of about 0.05 to about 0.3 V following pre-doping, and before use, compared to an Li/Li +  reference voltage.   
     
     
         12 . The energy storage device of  claim 11 , wherein the energy storage device has an open circuit cell voltage of 2.7 V to 2.95 V following pre-doping, and before use. 
     
     
         13 . The energy storage device of  claim 11 , wherein the first electrode and the second electrode each comprise a dry, free-standing electrode film and a current collector. 
     
     
         14 . The energy storage device of  claim 13 , wherein the first electrode and the second electrode each comprise an electrode film substantially free from processing additives. 
     
     
         15 . The energy storage device of  claim 11 , wherein the lithium salt is lithium hexafluorophosphate (LiPF 6 ). 
     
     
         16 . The energy storage device of  claim 11 , wherein the electrolyte further comprises a carbonate. 
     
     
         17 . The energy storage device of  claim 16 , wherein the carbonate is selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), vinyl ethylene carbonate (VEC), vinylene carbonate (VC), fluoroethylene carbonate (FEC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), and combinations thereof. 
     
     
         18 . The energy storage device of  claim 11 , wherein the first electrode comprises a carbon material selected from graphite, hard carbon, soft carbon, and combinations thereof. 
     
     
         19 . The energy storage device of  claim 11 , wherein the first electrode further comprises an electrical conductivity promoting material. 
     
     
         20 . The energy storage device of  claim 11 , wherein the energy storage device is a capacitor. 
     
     
         21 . A method for fabricating an energy storage device comprising:
 electrically coupling a lithium metal source and an electrode film; and   doping the electrode film with lithium ions to a predetermined electrode voltage of about 0.05 to about 0.3 V compared to an Li/Li +  reference voltage.   
     
     
         22 . The method of  claim 21 , wherein the electrode is an anode. 
     
     
         23 . The method of  claim 21 , wherein the electrode film is a capacitor electrode film. 
     
     
         24 . The method of  claim 21 , wherein the predetermined electrode voltage is selected to limit lithium metal plating and to limit gassing. 
     
     
         25 . The method of  claim 21 , wherein the electrode film is manufactured by a dry process. 
     
     
         26 . The method of  claim 25 , wherein the electrode film is a free-standing electrode film.